Tanneries in Tamil Nadu have some of the best water management systems in the world. While tanners across the world use 40 to 45 liters of water to process a kilogram of leather on an average, those in the state use half that quantity. Dr T Ramasami, Director, Central Leather Research Institute said, tanners in Tamil Nadu use on an average just 20-22 liters to process a kg of leather. The best of these use just 5 liters a kg.